Yasuo Sumi

Phase-dependent responses of Per1 and Per2 genes to a light-stimulus in the suprachiasmatic nucleus of the rat.

Single brief and discrete light treatments are sufficient to reset the overt mammalian rhythms of nocturnal rodents. In the present study, we examined the phase-dependent response of the mammalian clock genes, Per1 and Per2, to a brief strong light-stimulus (1000 lux) in the circadian oscillator center, the suprachiasmatic nucleus (SCN) of rats. Light-induced elevation of Per1 mRNA was observed through the subjective night (CT16, CT20 and CT0 (=CT24)) with a marked peak at the subjective dawn (CT0). However, the light influence was very limited for the induction of Per2; only weak elevation of Per2 mRNA was detected at CT16. The effect of light-stimulus on the Per1 gene was transient, and the effect was restricted to ventrolateral SCN neurons in both CT0 and CT16 after light exposure. Since it is known that these rats show a light-induced behavioral phase-shift throughout the subjective night with being strongest at subjective dawn, the present results suggest that the transient induction of Per1 in ventrolateral SCN neurons is a critical step in the resetting of the biological clock to environmental light-dark schedule.

Rhythmic expression of RORβ mRNA in the mice suprachiasmatic nucleus

Abstract The expression of the brain rich orphan nuclear receptor RORβ (retinoid-related orphan receptor beta) was investigated in the mouse brain by in situ hybridization using antisense cRNA probe. Positive RORβ mRNA signals were detected in various parts of the brain with high expression in the suprachiasmatic nucleus (SCN). In the SCN, RORβ mRNA signals showed a peak at early daytime (ZT/CT4) and a trough at early nighttime (ZT/CT16) in both light–dark and constant dark conditions. Light exposure at subjective night did not alter the expression level. These findings suggest that RORβ is a new member of a transcription factor possibly related to the circadian pacemaking system.

Laparoscopy-assisted distal gastrectomy in a patient with situs inversus totalis.

Introduction: We report on a patient with situs inversus totalis who underwent laparoscopic-assisted distal gastrectomy (LADG) involving standard lymph node dissection (LND) for early gastric cancer. Case Description: A 42-y-old man presented at the Department of Internal Medicine in our hospital with the diagnosis of early gastric cancer detected elsewhere by upper endoscopy. Endoscopic submucosal dissection for this early gastric cancer was performed at our hospital. Histopathological examination of the resected specimen yielded the diagnosis of type 0-IIc, T1b1(SM), ly (+), v (−), UL (−), HM0, VM0, R0, according to the Japanese Classification of Gastric Carcinoma. Additional surgery was deemed necessary, and he was referred to our department. Preoperative computed tomography showed no liver or lung metastasis. The preoperative diagnosis was cStage IA (pT1b1, cN0, cH0, cP0, and cM0). Standard LADG with LND (D1+No.7, 8a, 9) was performed successfully. Histological examination disclosed stage IB (pT1b1, pN1, sH0, sP0, and sM0). The patient was discharged on postoperative day 14 after an uneventful postoperative course. Eighteen months after the operation, he is doing well without recurrent gastric cancer. Conclusion: Laparoscopic surgery for gastric cancer with SIT should be considered a feasible, safe, and curative procedure.

Laparoscopic hemicolectomy in a patient with situs inversus totalis after open distal gastrectomy

Situs inversus totalis (SIT) is a rare anomaly in which the abdominal and thoracic cavity structures are opposite their usual positions. Occasionally, a few patients with a combination of this condition and malignant tumors have been encountered. Recently, several laparoscopic operations have been reported in patients with SIT. We report a case of an 83-year-old man with situs inversus totalis who developed colon cancer after open distal gastrectomy. Laparoscopic hemicolectomy with radical lymphadenectomy in such a patient was successfully performed by careful consideration of the mirror-image anatomy. Techniques themselves was not different from those in ordinary cases. Thus, curative laparoscopic surgery for colon cancer in the presence of situs inversus totalis is feasible and safe.

Laparoscopic complete mesocolic excision for right-sided colon cancer using a cranial approach: anatomical and embryological consideration

BackgroundComplete mesocolic excision (CME) with central vascular ligation (CVL) should be employed for the treatment of colon cancer patients because of its superior oncological outcomes. However, this technique is technically challenging in laparoscopic right hemicolectomy because of the anatomical complexity of the transverse mesocolon.MethodsWe focused on the embryology and anatomy of the transverse mesocolon to overcome the difficulty of this surgery. The validity and efficacy of a cranial approach in achieving CME with CVL in laparoscopic right hemicolectomy was elucidated from the embryological point of view.ResultsIn total, 28 consecutive patients with right-sided colon cancer were treated by laparoscopic right hemicolectomy using a cranial approach. There were no conversion to open surgery or switching to another approach. Using this approach, torsion and fusion of the transverse mesocolon, which occurred during embryological development, could be reversed and the complex anatomy of the transverse mesocolon could be simplified before performing CVL of colonic vessels.ConclusionsA cranial approach is considered valid and useful for CME with CVL in laparoscopic right hemicolectomy from the embryological point of view.

Prone position in thoracoscopic esophagectomy improves postoperative oxygenation and reduces pulmonary complications.

BackgroundWhile thoracoscopic esophagectomy is a widely performed surgical procedure, only few studies regarding the influence of body position on changes in circulation and breathing, after the surgery, have been reported. This study aimed at evaluating the effect of body position, during surgery, on the postoperative breathing functions of the chest.MethodsA total of 266 patients who underwent right-sided transthoracic esophagectomy for esophageal cancer from 2004 to 2012 were included in this study. Fifty-four of them underwent open thoracotomies in the left lateral decubitus position (Group O), 108 underwent thoracoscopic esophagectomy in the left lateral decubitus position (Group L) and 104 patients were treated by thoracoscopic esophagectomy in the prone position (Group P). Two patients in Group P, who presented with intra-operative bleeding and underwent thoracotomy, were subsequently excluded from the pulmonary function analysis.ResultsTwo patients in Group P had to be changed from the prone position to the lateral decubitus position and underwent thoracotomy in order to control intra-operative bleeding. Despite the significantly longer chest operation period in Group P, total blood loss was significantly lower in this group when compared to Groups O and L. Furthermore, patients in Group P presented with significantly lower water balance during the perioperative period and markedly higher SpO2/FiO2 ratio after the surgery. The incidence of respiratory complications was significantly higher in Group O when compared to the other two groups; however, no significant differences were observed between the Groups L and P.ConclusionThe findings of this study demonstrate that thoracoscopic esophagectomy in the prone position improves postoperative oxygenation and is therefore a potentially superior surgical approach.

Appendicitis with psoas abscess successfully treated by laparoscopic surgery.

Although acute appendicitis is a common disease, retroperitoneal abscesses are rarely observed. Here, we report a case consisting of a psoas abscess and cutaneous fistula caused by appendicitis. The patient was a 56-year-old male who was introduced to our institution due to an intractable right psoas abscess. Imaging tests had been performed over the previous 3 years; however, clinicians could not find the origin of the abscess and failed to resolve the problem. A successful operation was performed via a laparoscopic approach, and 17 mo have passed without recurrence. The advantage of laparoscopic surgery is well understood in cases of appendicitis with abscesses. However, the indication for laparoscopic approach is not clear for retroperitoneal abscesses. From our experience, we can conclude that appendicitis with retroperitoneal abscesses can be managed and treated using a laparoscopic approach.

Treating patients with advanced rectal cancer and lateral pelvic lymph nodes with preoperative chemoradiotherapy based on pretreatment imaging

Preoperative chemoradiotherapy (CRT) and lateral pelvic lymph node (LPLN) dissection (LPLD) based on pretreatment imaging are performed to improve oncological outcomes at our institution. However, the advantage of LPLD following preoperative CRT in advanced rectal cancer remains unclear. The objective of the present study was to assess the validity of this approach. Thirty-two patients with advanced rectal cancer were included in the study. All patients were treated with preoperative CRT and curative operation. Of these, 16 patients who were treated between August 2005 and June 2008 underwent LPLD on both sides (LPLD group). Sixteen patients who were treated between July 2008 and January 2013 underwent LPLD only on the side with suspected LPLN metastasis determined by pretreatment imaging; in cases without LPLN metastasis, only total mesorectal excision was performed (limited-LPLD group). The overall survival and relapse-free survival between the LPLD and the limited-LPLD groups were compared. Preoperative CRT was able to lower clinical lymph node status in 50% of the cases. In addition, pathological lymph node status did not exceed the pretreatment clinical lymph node status stage in the LPLD group. There were no differences in the overall survival and relapse-free survival between the two groups (P=0.729 and P=0.874, respectively). We conclude that multi-imaging studies have a very low risk of overlooking pathologically positive LPLN metastases. Therefore, limited LPLD is a feasible strategy for patients with advanced rectal cancer and suspicious LPLN metastases based on pretreatment imaging.

Laparoscopic partial resection for hemangioma in the third portion of the duodenum.

Benign duodenal tumors are rare and less common than malignant tumors. Furthermore, vascular lesions of the duodenum, including hemangiomas, are rare causes of gastrointestinal bleeding. This report describes a case with bleeding hemangiomas in the third portion of the duodenum and jejunum and their successful treatment using a laparoscopic approach. There is no report of totally laparoscopic resection for tumor in the third portion of duodenum. After performing a laparoscopic Kocher maneuver, the location of the duodenal hemangioma was confirmed by endoscopic and laparoscopic observation. The lesion was excised using ultrasonic coagulating shears and the defect in the duodenal wall was sutured laparoscopically. The hemangioma of the jejunum was treated extracorporeally through a 3.0 cm umbilical incision. The operating time was 241 min and blood loss was negligible. The postoperative course was uneventful. For benign duodenal tumors in the third portion, if endoscopic resection is not adapted, this less invasive technique may be a standard treatment.

The learning effect of using stereoscopic vision in the early phase of laparoscopic surgical training for novices

BackgroundRecently to improve depth perception, the performance of three-dimensional (3D) laparoscopic surgeries has increased. However, the effects of laparoscopic training using 3D are still unclear. This study aimed to clarify the effects of using a 3D monitor among novices in the early phase of training.MethodsParticipants were 40 novices who had never performed laparoscopic surgery (20 medical students and 20 junior residents). Three laparoscopic phantom tasks (task 1: touching markers on a flat disk with a rod; task 2: straight rod transfer through a single loop; and task 3: curved rod transfer through two loops) in the training box were performed ten times, respectively. Performances were recorded by an optical position tracker. The participants were randomly divided into two groups: one group performed each task five times initially under a 2D system (2D start group), and the other group performed each task five times under a 3D system (3D start group). Both groups then performed the same task five times. After the trial, we evaluated the performance scores (operative time, path length of forceps, and technical errors) and the learning curves for both groups.ResultsScores for all tasks performed under the 3D system were significantly better than scores for tasks using the 2D system. Scores for each task in the 2D start group improved after switching to the 3D system. However, scores for each task in the 3D start group were worse after switching to the 2D system, especially scores related to technical errors.ConclusionsThe stereoscopic vision improved laparoscopic surgical techniques of novices from the early phase of training. However, the performance of novices trained only by 3D worsened by changing to the 2D environment.